For medical, nursing and physiotherapy undergraduates, and postgraduates

1. INTRODUCTION
TO
ABDOMEN

2. LANDMARKS

3. UMBILICUS

4. HOLDENS LINE

5. CUTANEOUS NERVES
• Lower six thoracic nerves
– Lower five intercostal
– Subcostal nerve
• First Lumbar nerve

6. CUTANEOUS ARTERIES
• Anterior Cutaneous Arteries
• Lateral Cutaneous Arteries
• Superficial Inguinal Arteries
– Superficial Epigastric
– Superficial External Pudendal
– Superficial Circumflex Iliac
• Great Saphenous Vein

7. MUSCLES
1. External oblique
2. Internal oblique
3. Transversus abdominis
4. Rectus abdominis
5. Cremaster
6. Pyramidalis

8. EXTERNAL OBLIQUE
• Origin –
• Eight fleshy slips from outer surface of shaft of
lower eight ribs
• Downwards, forwards and medially
• Nerve supply : Lower six thoracic nerves

9. EXTERNAL OBLIQUE
• Insertion – Most fibres form broad aponeurosis
and inserted from above downwards from :
1. Xiphoid process
2. Linea alba
3. Pubic symphysis
4. Pubic crest
5. Pectinate line of the pubis
• Lower fibres – directly into anterior 2/3rd of outer
lip of iliac crest

11. INTERNAL OBLIQUE
• Origin –
1. Lateral 2/3rd of Inguinal ligament
2. Anterior 2/3rd of Intermediate area of the iliac
crest
3. Thoraco-lumbar fascia
• Upwards, forwards and medially
• Nerve supply :
1. Lower six thoracic nerves
2. First Lumbar nerve

12. INTERNAL OBLIQUE
• Insertion –
• Uppermost fibres – directly into the lower 3 or 4
ribs and their cartilages.
• Greater part of muscle ends in broad
aponeurosis and inserts in :
– Seventh, eight and ninth costal cartilages
– Xiphoid process
– Linea alba
– Pubic crest
– Pectinate line of pubis

14. TRANSVERSUS ABDOMINIS
• Origin –
1. Lateral 1/3rd of Inguinal ligament
2. Anterior 2/3rd of Inner lip of the iliac crest
3. Thoraco-lumbar fascia
4. Inner surfaces of lower six cartilages
• Directed horizontally forwards
• Nerve supply :
1. Lower six thoracic nerves
2. First Lumbar nerve

15. TRANSVERSUS ABDOMINIS
• Insertion –
• Greater part of muscle ends in broad
aponeurosis and inserts in :
– Xiphoid process
– Linea alba
– Pubic crest
– Pectinate line of pubis
• Lowest fibres – they fuse with the lowest fibres of
Internal oblique to form Conjoint tendon

18. ACTION
1. Retention of viscera in position
2. Protection of viscera from external injury
3. Compression – increase intra-abdominal
pressure and compress the viscera in act of
vomiting, micturition, defaecation.
4. Action on vertebral column :
1. Acting B/L – flexion of lumbar vertebrae
2. Acting U/L – Lateral flexion of trunk
3. Rotation of trunk

19. RECTUS ABDOMINIS
• Origin – Two tendinous heads
• Lateral head – Lateral part of the pubic crest
• Medial head – Medial part of pubic crest and
Anterior Pubic ligament
• Directed vertically upwards
• Nerve supply :
1. Lower six or seven thoracic nerves

20. RECTUS ABDOMINIS
• Insertion – as four fleshy slips arranged in a
horizontal line
• Most medial slip – anterior surface of xiphoid
process
• Remaining slips – from lateral to medial side
to the 5th, 6th and 7th costal cartilages.
• Directed vertically upwards
• Nerve supply :
1. Lower five intercostal and subcostal nerves

21. RECTUS ABDOMINIS
• Action –
1. Protection to abdominal viscera
2. Compress abdominal cavity and maintain
intra- abdominal pressure
3. Produce flexion of the vertebral column

23. PYRAMIDALIS
• Origin – anterior surface of body of pubis
• Pass upwards and medially
• Insertion – Linea alba
• Nerve supply – Subcostal nerve
• Action – Tensor Of Linea Alba

25. CREMASTER
• Origin –
• Superficial loop – Middle 1/3rd of upper surface
of Inguinal ligament
• Deep loops – public tubercle, pubic crest,
conjoint tendon
• Nerve supply – Genital branch of genito-femoral
nerve
• Action –helps to suspend the testes and elevate
it.

27. RECTUS SHEATH
• It is a aponeurotic sheath covering Rectus
abdominis
• Two walls :
• Anterior wall
• Posterior wall
• Lateral wall

28. RECTUS SHEATH
• Anterior wall - incomplete and attached to
tendinous intersections of Rectus Abdominis
muscle.
• Posterior wall – incomplete, free from rectus
abdominis
• Fusion of all the aponeuroses in midline is
called as Linea alba

29. RECTUS SHEATH
• Anterior wall - incomplete and attached to
tendinous intersections of Rectus Abdominis
muscle.
• Posterior wall – incomplete, free from rectus
abdominis
• Fusion of all the aponeuroses in midline is
called as Linea alba

30. RECTUS SHEATH
• Lateral wall – Extends till Linea Semilunaris,
extending from tip of 9th costal cartilage to
pubic tubercle.

31. FORMATION

32. FORMATION

33. CONTENTS
• Muscles :
1. Rectus abdominis
2. Pyramidalis
• Arteries :
1. Superior epigastric artery
2. Inferior epigastric artery

34. CONTENTS
• Veins :
1. Superior epigastric vein – Internal thoracic
vein
2. Inferior epigastric artery – External iliac vein
• Nerves :
• Terminal parts of lower six thoracic nerves

35. FUNCTIONS
1. Maintains strength of the naterior abdominal
wall
2. Checks bowing of Rectus muscle during its
contraction
3. Increases the efficiency of rectus abdominis
muscle